SINGLE CAPACITY BALANCING IN A REDOX FLOW BATTERY
A method of operating an all vanadium redox flow battery includes providing an all vanadium redox flow battery comprising an anolyte storage tank including a volume of anolyte and a catholyte storage tank including a volume of catholyte; an electrochemical cell in fluid communication with the anolyte and catholyte storage tanks; and a predetermined range for the ratio of vanadium concentration between the anolyte and the catholyte; and transferring an amount of catholyte from the catholyte storage tank to the anolyte storage tank, or an amount of anolyte from the anolyte storage tank to the catholyte storage tank, to restore the ratio of vanadium concentration to the predetermined range. An all vanadium redox flow battery system includes means for transferring anolyte and catholyte between the anolyte and catholyte storage tanks to maintain a predetermined range for the ratio of vanadium concentration between the anolyte and the catholyte.
1 . A method of operating an all vanadium redox flow battery, comprising:
providing an all vanadium redox flow battery comprising
an anolyte storage tank including a volume of anolyte and a catholyte storage tank including a volume of catholyte;
an electrochemical cell in fluid communication with the anolyte and catholyte storage tanks; and
a predetermined range for the ratio of vanadium concentration between the anolyte and the catholyte; and
transferring an amount of catholyte from the catholyte storage tank to the anolyte storage tank, or an amount of anolyte from the anolyte storage tank to the catholyte storage tank, to restore the ratio of vanadium concentration to the predetermined range.
2 - 9 . (canceled)
10 . An all vanadium redox flow battery system, comprising:
an anolyte storage tank configured for containing a quantity of an anolyte;
a catholyte storage tank configured for containing a quantity of a catholyte;
an electrochemical cell configured for fluid communication with the anolyte and catholyte storage tanks; and
a conduit interconnecting the anolyte storage tank and catholyte storage tank, wherein the conduit is configured to allow a liquid to flow between the anolyte and catholyte storage tanks in response to a condition to maintain a predetermined range for the ratio of vanadium concentration between the anolyte and the catholyte.
11 . The system of claim 10 , wherein the conduit is configured to allow the transfer of liquid and gas.
12 . The system of claim 10 , wherein the conduit is positioned to include a gas travel path above the liquid level of the anolyte and catholyte storage tanks.
13 . The system of claim 10 , wherein the quantity of anolyte and the quantity of catholyte are based on the predetermined range for the ratio of vanadium concentration.
14 . The system of claim 10 , wherein the volume capacity of the anolyte tank and the volume capacity of the catholyte tank are selected based on predetermined range for the ratio of vanadium concentration.
15 . The system of claim 10 , further comprising a valve associated with the conduit to conditionally regulate flow between the anolyte and the catholyte storage tanks.
16 . The system of claim 15 , wherein the valve is configured to be controllable in response to receiving control signals.
17 . The system of claim 10 , further comprising a pump associated with the conduit to conditionally regulate flow between the anolyte and the catholyte storage tanks.
18 . The system of claim 17 , wherein the pump is configured to be controllable in response to receiving control signals.
19 . The system of claim 10 , wherein the conduit is configured for passive transfer of anolyte or catholyte between the anolyte and catholyte storage tanks.
20 . The system of claim 10 , wherein the conduit is configured for active transfer of anolyte or catholyte between the anolyte and catholyte storage tanks.
21 . The system of claim 10 , wherein the conduit allows catholyte to flow into the anolyte storage tank, or anolyte to flow into the catholyte storage tank, in response to the condition.
22 . The system of claim 10 , wherein system may be configurable as avanadium-sulfate redox flow battery, vanadium-chloride redox flow battery, vanadium-mixed sulfate and chloride redox flow battery.
23 . An all vanadium redox flow battery system, comprising a plurality of flow battery systems of claim 10 , each redox flow battery system in electrical communication with at least one other redox flow battery system.
24 . The system of claim 23 , wherein each redox flow battery is not in fluid communication with any other redox flow battery system.
25 . The system of claim 23 , wherein the plurality of redox flow battery systems is electrically connected in series.
26 . The system of claim 23 , wherein the condition includes a difference in an open circuit voltage value between at least first and second redox flow battery systems in the plurality of redox flow batter systems.
27 . An all vanadium redox flow battery system, comprising:
an anolyte storage tank configured for containing a quantity of an anolyte;
a catholyte storage tank configured for containing a quantity of a catholyte;
an electrochemical cell in fluid communication with the anolyte and catholyte storage tanks; and
means for transferring anolyte and catholyte between the anolyte and catholyte storage tanks to maintain a predetermined range for the ratio of vanadium concentration between the anolyte and the catholyte.
28 . The system of claim 27 , wherein the means for transferring is a means for passively transferring anolyte and catholyte between the anolyte and catholyte storage tanks.
29 . The system of claim 27 , wherein the means for transferring is a means for actively transferring anolyte and catholyte between the anolyte and catholyte storage tanks.
30 . The system of claim 29 , wherein the means for actively balancing includes one or more of a pump and a control valve.